1 Gibbs Free Energy and Spontaneity and the meaning of the universe…

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1 Gibbs Free Energy and Spontaneity and the meaning of the universe…

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2 Relationship Between  S surr & H Water  S Surr q(system)   S surr affected by heat transfer into or out of closed system Entropy of the surroundings will be affected only by the heat transferred into or out of any closed system. Heat added to surroundings: K.E. surr increases; Molecules are moving faster. K.E. surr increases; Molecules are moving faster. Disorder increases since there is more randomness Disorder increases since there is more randomness Entropy increases. Entropy increases. Note: q p = -  H sys   S surr

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6 J. Willard Gibbs The Free Energy change (  G) is a measure of spontaneity of a process and of the useful energy available from such a process. J. Willard Gibbs (1839-1903) was not particularly well known in his day, nor is his name widely recognized today, yet he is considered by some to be among the greatest scientists ever born in America. He was awarded th first doctorate in engineering granted in the United States, by Yale University. Gibbs became a professor of mathematical physics at Yale when he was 32 years old and began to publish a series of papers related to thermodynamics and equilibrium. Perhaps because his work was so theoretical, it was largely unappreciated at the time, though its great value was recognized by James Clerk Maxwell. Gibb’s work, if not his name, remains current and vital to this day.

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1515 Free Energy and work Science and Technology use physical and or chemical processes because these can do work. Economics: To make money €, the work to be preformed must be a possibility and efficient.  G provides information on spontaneity:  G (+) or (-) provides information on the spontaneity of the process @  P,  T = 0 Wasting time:  G is useful because it prevents the wasted effort on process with no inherent tendency to occur.  G isn’t whole story, Kinetics also important: Note that thermodynamically favorable process may still not occur to any appreciable extent because of the Kinetics. - It makes sense to find a catalyst to speed up the reaction. - It makes sense to find a catalyst to speed up the reaction. - Prevents wasting time and resource of seeking a catalyst on a reaction that won’t even work. - Prevents wasting time and resource of seeking a catalyst on a reaction that won’t even work.